Seiji Oka

Person

Yokohama, JP

People

Patents Grantslast 30 patents

Information Patent Grant
Toner collecting and reusing device for use in an image forming app...
- Patent number 6,108,511
- Issue date Aug 22, 2000
- Ricoh Company, Ltd.
- Akio Kutsuwada
- G03 - PHOTOGRAPHY CINEMATOGRAPHY ELECTROGRAPHY HOLOGRAPHY
Information Patent Grant
Recyclable toner container for an image forming apparatus
- Patent number 5,983,059
- Issue date Nov 9, 1999
- Ricoh Company, Ltd.
- Seiji Oka
- G03 - PHOTOGRAPHY CINEMATOGRAPHY ELECTROGRAPHY HOLOGRAPHY
Information Patent Grant
Developing machine which uses a developing agent including a toner...
- Patent number 5,822,664
- Issue date Oct 13, 1998
- Ricoh Company, Ltd.
- Seiji Oka
- G03 - PHOTOGRAPHY CINEMATOGRAPHY ELECTROGRAPHY HOLOGRAPHY
Information Patent Grant
Developing device for an image forming apparatus having developer d...
- Patent number 5,805,965
- Issue date Sep 8, 1998
- Ricoh Company, Ltd.
- Kiyonori Tsuda
- G03 - PHOTOGRAPHY CINEMATOGRAPHY ELECTROGRAPHY HOLOGRAPHY
Information Patent Grant
Developing device using a toner and carrier mixture
- Patent number 5,771,426
- Issue date Jun 23, 1998
- Ricoh Company, Ltd.
- Seiji Oka
- G03 - PHOTOGRAPHY CINEMATOGRAPHY ELECTROGRAPHY HOLOGRAPHY
Information Patent Grant
Developing device capable of automatic toner content control
- Patent number 5,771,429
- Issue date Jun 23, 1998
- Ricoh Company, Ltd.
- Hajime Oyama
- G03 - PHOTOGRAPHY CINEMATOGRAPHY ELECTROGRAPHY HOLOGRAPHY
Information Patent Grant
Developing device for an image forming apparatus
- Patent number 5,758,241
- Issue date May 26, 1998
- Ricoh Company, Ltd.
- Hajime Oyama
- G03 - PHOTOGRAPHY CINEMATOGRAPHY ELECTROGRAPHY HOLOGRAPHY
Information Patent Grant
Developing device for an image forming apparatus and toner cartridge
- Patent number 5,659,860
- Issue date Aug 19, 1997
- Ricoh Company, Ltd.
- Fumihiro Sasaki
- G03 - PHOTOGRAPHY CINEMATOGRAPHY ELECTROGRAPHY HOLOGRAPHY
Information Patent Grant
Image forming apparatus having toner recycling device with electros...
- Patent number 5,555,469
- Issue date Sep 10, 1996
- Ricoh Company, Ltd.
- Fumihiko Ishikawa
- G03 - PHOTOGRAPHY CINEMATOGRAPHY ELECTROGRAPHY HOLOGRAPHY
Information Patent Grant
Developing unit for an image forming apparatus
- Patent number 5,416,568
- Issue date May 16, 1995
- Ricoh Company, Ltd.
- Shigeru Yoshiki
- G03 - PHOTOGRAPHY CINEMATOGRAPHY ELECTROGRAPHY HOLOGRAPHY
Information Patent Grant
Image forming apparatus
- Patent number 5,255,059
- Issue date Oct 19, 1993
- Ricoh Company, Ltd.
- Tsukuru Kai
- G03 - PHOTOGRAPHY CINEMATOGRAPHY ELECTROGRAPHY HOLOGRAPHY
Information Patent Grant
Image forming apparatus with replaceable process units
- Patent number 5,235,384
- Issue date Aug 10, 1993
- Ricoh Company, Ltd.
- Seiji Oka
- G03 - PHOTOGRAPHY CINEMATOGRAPHY ELECTROGRAPHY HOLOGRAPHY
Information Patent Grant
Developing apparatus
- Patent number 5,109,254
- Issue date Apr 28, 1992
- Ricoh Company, Ltd.
- Seiji Oka
- G03 - PHOTOGRAPHY CINEMATOGRAPHY ELECTROGRAPHY HOLOGRAPHY
Information Patent Grant
Toner supply device for electrophotographic equipment
- Patent number 5,077,584
- Issue date Dec 31, 1991
- Ricoh Company, Ltd.
- Masaru Tanaka
- G03 - PHOTOGRAPHY CINEMATOGRAPHY ELECTROGRAPHY HOLOGRAPHY
Information Patent Grant
Toner cartridge
- Patent number 4,969,557
- Issue date Nov 13, 1990
- Ricoh Co., Ltd.
- Seiji Oka
- G03 - PHOTOGRAPHY CINEMATOGRAPHY ELECTROGRAPHY HOLOGRAPHY
Information Patent Grant
Toner cartridge
- Patent number 4,799,608
- Issue date Jan 24, 1989
- Ricoh Company, Ltd.
- Seiji Oka
- G03 - PHOTOGRAPHY CINEMATOGRAPHY ELECTROGRAPHY HOLOGRAPHY
Information Patent Grant
Magnetic brush development device for electrostatic latent images
- Patent number 4,800,411
- Issue date Jan 24, 1989
- Ricoh Company, Ltd.
- Masaru Tanaka
- G06 - COMPUTING CALCULATING COUNTING
Information Patent Grant
Toner cartridge
- Patent number 4,650,070
- Issue date Mar 17, 1987
- Ricoh Company, Ltd.
- Seiji Oka
- G03 - PHOTOGRAPHY CINEMATOGRAPHY ELECTROGRAPHY HOLOGRAPHY

Person

Patents Grantslast 30 patents

Toner collecting and reusing device for use in an image forming app...

Recyclable toner container for an image forming apparatus

Developing machine which uses a developing agent including a toner...

Developing device for an image forming apparatus having developer d...

Developing device using a toner and carrier mixture

Developing device capable of automatic toner content control

Developing device for an image forming apparatus

Developing device for an image forming apparatus and toner cartridge

Image forming apparatus having toner recycling device with electros...

Developing unit for an image forming apparatus

Image forming apparatus

Image forming apparatus with replaceable process units

Developing apparatus

Toner supply device for electrophotographic equipment

Toner cartridge

Toner cartridge

Magnetic brush development device for electrostatic latent images

Toner cartridge